"But why American, European, Canadian, and Japanese space travelers are called astronauts is a little mystifying — and a little lost to history. Here’s what we know (and don’t know) about the origin of the word ‘astronaut,’ and what it means to those few who sail through space.
Jennifer Ross-Nazzal, Ph.D., a historian at NASA Johnson Space Center, says ‘astronaut’ dates back to late 1958, when NASA was still in its infancy. The agency used the name ‘astronaut’ in drafts of a job listing that called for applicants to its new astronaut program. Ross-Nazzal says that NASA also considered ‘cosmonaut,’ or universe sailor, before adopting the name astronaut."
Jennifer Ross-Nazzal, Ph.D., a historian at NASA Johnson Space Center, says ‘astronaut’ dates back to late 1958, when NASA was still in its infancy. The agency used the name ‘astronaut’ in drafts of a job listing that called for applicants to its new astronaut program. Ross-Nazzal says that NASA also considered ‘cosmonaut,’ or universe sailor, before adopting the name astronaut."